The Palestinian militants said they released Lifshitz, 85, and a second woman Nurit Cooper, 79, on health grounds, after taking them and more than 200 others hostage during an Oct. 7 gun rampage in Israel in which the militants killed 1,400 people.

Lifshitz and her 83-year old husband, Oded, were kidnapped from their home at the Nir Oz kibbutz, close to the border with Gaza in southern Israel, the Israeli prime minister's office said late on Monday. Oded remained captive, it added.

"They are human rights activists, peace activists for all their life," grandson Daniel Lifshitz told Reuters in Tel Aviv before the release was confirmed.

"For more than a decade, they took ... sick Palestinians from the Gaza Strip, not from the West Bank, from the Gaza Strip every week from the Erez border to the hospitals in Israel to get treatment for their disease, for cancer, for anything," he added.

Hamas posted a video on its Telegram page appearing to show Lifshitz being handed over to workers with the International Committee of the Red Cross (ICRC), which said it helped transport them out of Gaza.

In the video, a man carrying a long gun and wearing a bullet proof vest emblazoned with a Hamas flag escorts Lifshitz to a white ICRC van. Before entering the van, she reaches her hand out to the man and tells him "salam," Arabic for peace.

Reuters could not immediately verify the video.

In a message passed to Reuters by a family friend, Lifshitz's daughter Sharon in London wrote: "While I cannot put into words the relief that she is now safe, I will remain focused on securing the release of my father and all those - some 200 innocent people - who remain hostages in Gaza."

The two women were the third and fourth hostages to be freed. On Friday, Hamas on Friday released an American woman and her daughter.

At least 5,087 Palestinians have been killed in two weeks of Israeli strikes, including 2,055 children, the Hamas-run health ministry said.